The site is surrounded in the north by a group of hills which slope upward from southwest to northeast. The slopes of the hills vary from 10o to 45o. The ridges vary up and down with smooth round hill tops. Within 2 km of the site the elevation is generally 185 to 400 m. The summit, called Pai Ya Shan, is 707 m PRD. Due to the construction of the Daya Bay and LingAo NPPs, the southwest to southeast coast regions, where the access to the experimental sites will be located, are levelled, with height in the range 6.6-20 m PRD.
According to the available geological structure maps, the near-detector site lies in the southwest portion of the Lianhua Mountain fault, in the south side of the Pai Ya Shan. It is on the massif between the Wuhua - Shenzhen and Da Pu - Haifeng sub-faults. Close to the site there are very few faults and they are not directly related to the above mentioned faults. Hence the geological structure of the near site is rather simple. The earth surface exploration and trenching exposure show that the landforms and terrains are in good condition. The site geology structure is simple. There are no karsts, landslides, collapsing, mud slides, empty pockets, ground sinking asymmetry, hot springs, etc., that would affect negatively the stability of the site region. There are only individual loose granites which are separately distributed due to globular weathering.
All the geological data of Daya Bay are taken from "Atlas of Natural Resources and Economic Development of Shenzhen", Science Press, Beijing, China, 1985 (#5434-91).
Rock indices (granite, sample from Daya Bay and Ling Ao quarry):
Density: 26.3 kN/m3
Pressure resistance strength of a saturated single stalk: 208.4 MPa
Pressure resistance strength of a dry single stalk: 212.1 MPa
Softening coefficient: 0.98
Elastic modulus: 61500 MPa
Poisson ratio: 0.28
More details of Daya Bay rock properties.